Processors and compiling methods for processors

Compiling apparatus, for converting a source program into a corresponding object program to be executed by a processor having a plurality of execution units operable in parallel, the object program including a loop kernel block and a basic block preceding said loop kernel block, and the basic block including a producer instruction and the loop kernel block including a consumer instruction requiring a value produced by said producer instruction, which apparatus comprises:

• a loop kernel block scheduling unit which schedules the instructions of the loop kernel block and which is operable to schedule said consumer instruction for execution in a first one of the execution units;
• and
• a basic block block scheduling unit which schedules the instructions of said basic block after said scheduling of the loop-kernel-block instructions and which is operable to schedule said producer instruction for execution in a second one of the execution units and which is further operable to schedule at least one move instruction so as to create an availability chain within said basic block for moving the required value to a first point accessible by said consumer instruction from a second point accessible by said producer instruction.

A compiling method, for converting a source program into a corresponding object program to be executed by a processor having a plurality of execution units operable in parallel, the object program including a loop kernel block and a basic block preceding said loop kernel block, and the basic block including a producer instruction and the loop kernel block including a consumer instruction requiring a value produced by said producer instruction, which method is carried out by electronic data processing apparatus and comprises the steps of:

• (a) scheduling the instructions of the loop kernel block, including scheduling said consumer instruction for execution by a first one of the execution units;
• and
• (b) after step (a) scheduling the instructions of the basic block, including selecting, in dependence upon the scheduling in step (a) of said consumer instruction for execution by said first execution unit, one of the plurality of execution units to execute said producer instruction and scheduling said producer instruction for execution by the selected execution unit.

Compiling apparatus, for converting a source program into a corresponding object program to be executed by a processor having a plurality of execution units operable in parallel, the object program including a loop kernel block and a basic block preceding said loop kernel block, and the basic block including a producer instruction and the loop kernel block including a consumer instruction requiring a value produced by said producer instruction, which apparatus comprises:

• a loop kernel scheduling block which schedules the instructions of the loop kernel block and which is operable to schedule said consumer instruction for execution in a first one of the execution units;
• and
• a basic block scheduling unit which schedules the instructions of said basic block after said scheduling of the loop-kernel-block instructions and which is operable to select, in dependence upon the scheduling of said consumer instruction for execution by said first execution unit, one of the plurality of execution units to execute said producer instruction and which is further operable to schedule said producer instruction for execution by the selected execution unit.